DE102017118071B4 - Touch sensor and method of manufacturing the same, and touch display panel - Google Patents

Abstract

A touch sensor comprising: a substrate (100) comprising a plurality of grooves (101) having a stripe shape and crossing each other to form a lattice shape, a first propagation control layer (103) formed on an inner wall of each of the plurality of grooves (101), and a touch electrode (102) filled in the groove (101), the first spread control layer (103) being disposed between the groove (101) and the touch electrode (102), wherein a spread angle between the touch electrode (102 ) in a released state and the first spread control layer (103) is denoted by α, and a spread angle between the touch electrode (102) in a released state and the substrate (100) is denoted by β, where α is not equal to β, and the touch electrode (102) in dissolved state is a solution formed by dissolving electrode material of the touch electrode (102) in a solvent, wherein the spreading angle in dissolved state is defined as a between a tangent (T1) of a gas-liquid interface at a crossing point (O) of gas phase, the liquid phase and the solid phase, and a solid-liquid boundary line (T2) passing through the liquid.

Description

technical field

The present disclosure relates to the field of display technology, and more particularly to a touch sensor and a method of manufacturing the same, and a touch display panel.

background

Currently, in order to realize a touch function in an organic light emitting diode flexible display panel, it is generally required to laminate a layer of a touch module on the display panel, resulting in the flexible display panel not being made thin. In order to make a flexible touch display panel light and thin, integrated technology is adopted to replace the traditional module lamination technology. The existing integrated technologies are mainly divided into the following two types.

In one type, a touch electrode is integrated into a protective film layer, a polarizer, or a glass cover plate. While this allows a flexible display product to be made thinner to some extent, this approach involves a relatively high cost of manufacturing the protective film layer, polarizer, and cover plate glass.

According to the other approach, a touch electrode is integrated on a surface of a thin film encapsulation layer, and the touch electrode needs to be subjected to photo-etching and wet-etching processes. However, a yellow light phenomenon occurring in the photoetching process and the like can damage a light-emitting layer of an organic light-emitting display panel, while acidic or basic chemical liquid during the wet process can easily damage each of the film layers in the thin-film encapsulating layer.

Summary

The present disclosure provides a touch sensor and a method for manufacturing the same, and a touch display panel to simplify the manufacturing process of the touch sensor, increase a connection reliability of the touch electrode, and reduce damage caused by the manufacturing process of the touch electrode to film-layer materials of a thin-film encapsulation layer and film-layer materials of a light-emitting element of an organic light emitting display panel, thereby improving the operational reliability of the organic light emitting display panel.

• eine erste Ausbreitungssteuerungsschicht, die auf einer Innenwand jeder der Vielzahl von Nuten angeordnet ist, und
• eine in die Nut eingefüllte Berührungselektrode, wobei die erste Ausbreitungssteuerungsschicht zwischen der Nut und der Berührungselektrode angeordnet ist, wobei
• ein Ausbreitungswinkel zwischen der Berührungselektrode in gelöstem Zustand und der ersten Ausbreitungssteuerungsschicht mit α und ein Ausbreitungswinkel zwischen der Berührungselektrode in gelöstem Zustand und dem Substrat mit β bezeichnet ist, wobei α ungleich β ist.

In a first aspect, an embodiment of the present disclosure provides a touch sensor, comprising: a substrate, the substrate having a plurality of grooves having a stripe shape and interconnected to define a lattice shape,

• a first spreading control layer disposed on an inner wall of each of the plurality of grooves, and
• a touch electrode filled in the groove, the first propagation control layer being interposed between the groove and the touch electrode, wherein
• a spread angle between the touch electrode in a released state and the first spread control layer is denoted by α, and a spread angle between the touch electrode in a released state and the substrate is denoted by β, where α is not equal to β.

The touch electrode in a dissolved state is a solution formed by dissolving electrode material of the touch electrode in an organic solvent.

In a second aspect, an embodiment of the present disclosure further provides a touch display panel comprising: a layer of light emitting elements and a thin film encapsulation layer covering the layer of light emitting elements, wherein the touch sensor is formed directly on a surface of the thin film encapsulation layer.

In a third aspect, an embodiment of the present disclosure further provides a method of manufacturing a touch sensor, comprising: forming a substrate,

forming a plurality of stripe-shaped grooves on a surface of the substrate, the plurality of grooves being interconnected to define a lattice shape,

forming a first propagation control layer, the first propagation control layer being formed on an inner wall of the groove, and

forming a touch electrode, wherein the touch electrode is filled in the groove, and the first propagation control layer is arranged between the groove and the touch electrode.

An angle of spread between the touch electrode in a released state and the first spread control layer is denoted by α, and an angle of spread between the touch electrode in a released state and the substrate is denoted by β, where α is not equal to β.

The touch electrode in a dissolved state is a solution formed by dissolving electrode material of the touch electrode in an organic solvent.

The embodiments of the present disclosure provide a touch sensor and a method of manufacturing the same, and a touch display panel. A groove is arranged on a substrate of the touch sensor, a touch electrode is formed in the groove, and before forming the touch electrode, a first propagation control layer is arranged on an inner wall of the groove. A propagation angle between the touch electrode in a released state and the first propagation control layer is unequal to a propagation angle between the touch electrode in a released state and the substrate, so that the touch electrode in a released state has different propagation characteristics with respect to the groove and the substrate surface. Therefore, better control of formation of the touch electrode can be realized, manufacture of the touch electrode is simplified, processing stability of the touch electrode is enhanced, the touch electrode can be evenly distributed in the groove, and a risk of disconnection of the touch electrode is greatly reduced, thereby improving touch reliability of the touch electrode Touch electrode is improved.

character list

• 1A 12 is a top view of a touch sensor according to an embodiment of the present disclosure;
• 1B 12 is a cross-sectional view taken along AA 1A ;
• 2A 12 is a schematic representation of a propagation angle α between the touch electrode in the released state and the first propagation control layer, according to an embodiment of the present disclosure;
• 2 B 12 is a schematic representation of a propagation angle β between the touch electrode in the released state and the substrate, according to an embodiment of the present disclosure;
• 3A 12 is a schematic representation of a groove according to an embodiment of the present disclosure;
• 3B 12 is a schematic representation of another groove according to an embodiment of the present disclosure;
• 3C 12 is a cross-sectional view taken along AA 3B ;
• 4 12 is a schematic representation of another groove according to an embodiment of the present disclosure;
• 5 12 shows a touch display panel according to embodiments of the present disclosure;
• 6 12 shows another touch display panel according to the embodiments of the present disclosure; and
• 7 FIG. 1 is a schematic flow diagram of a method of manufacturing a touch sensor according to embodiments of the present disclosure.

Detailed description of the embodiments

The present disclosure will be described in more detail below with reference to the accompanying drawings and embodiments. It is noted that the embodiments mentioned herein are not intended to limit the present disclosure, but are only intended to explain it. In addition, it is noted that for the sake of simplifying the description, drawings do not show all parts, only parts pertinent to the present disclosure. Furthermore, for the purpose of clearer description, the same reference number will be used in different drawings.

An embodiment of the present disclosure provides a touch sensor, comprising: a substrate, the substrate having a plurality of grooves having a stripe shape and crossing each other to define a lattice shape,

a first spreading control layer disposed on an inner wall of each of the plurality of grooves, and

a touch electrode filled in the groove, wherein the first propagation control layer is interposed between the groove and the touch electrode.

An angle of spread between the touch electrode in a released state and the first spread control layer is denoted by α, and an angle of spread between the touch electrode in a released state and the substrate is denoted by β, where α is not equal to β.

The touch electrode in a dissolved state refers to a solution state formed by dissolving an electrode material of the touch electrode in a solvent. Optionally, the solvent can be an organic solvent, which can be one or more of ethyl cellulose, cellulose nitrate, polyvinyl acetate, ketone resin, and polyphthaleinamine resin. It is noted that the touch electrode in the dissolved state is hereinafter referred to as “electrode material solution”.

Basically, the touch electrode of the touch sensor is formed directly on the surface of the substrate of the touch sensor. The touch electrode material comprises transparent indium tin oxide. However, in a flexible display panel, a metal mesh electrode with good flexibility and lower impedance can be used to increase the flexural strength of the touch electrode. In the manufacturing process of the metal grid, a screen printing process can be used with the direct application of metal printing ink. Alternatively, the metal can be applied as a full coating to the substrate as a thin film and then superfluous parts washed away via a yellow light photolithography process to create the grating. Any of the above approaches may have a detrimental effect on the light-emitting element when the metal mesh electrode is formed directly in the organic light-emitting display panel.

In the embodiments of the present disclosure, the touch electrode is formed in the groove on the substrate by inkjet printing, the electrode material of the touch electrode can be metal, the electrode material of the touch electrode is dissolved in an organic solvent to form electrode material solution of the touch electrode, and then the electrode material solution is jetted and printed into the groove of the substrate. Liquid entering the groove smoothly flows along an inner wall of the groove to form a uniform electrode shape, and then hardens and the organic solvent volatilizes. In this way, the touch electrode is formed. In the embodiments of the present disclosure, a first spread control layer is disposed on the inner wall of the groove before the electrode material solution is jetted and printed into the groove. The first spreading control layer can regulate spreading properties of the electrode material solution and the groove. In this way, a flow rate and distribution uniformity of the electrode material solution in the groove are regulated and controlled, uniformity of the formed touch electrode is ensured, breakage of the touch electrode is reduced, uniform impedance of each electrode is ensured, and touch performance of the touch sensor is improved.

The embodiments of the present invention will be described in detail in combination with the accompanying drawings. 1A FIG. 12 is a top view of a touch sensor according to an embodiment of the present disclosure. 1B 12 is a cross-sectional view taken along AA 1 , 2A 12 is a schematic representation of a propagation angle α between the touch electrode in the released state and the first propagation control layer according to an embodiment of the present disclosure and 2 B 12 is a schematic representation of a propagation angle β between the touch electrode in the released state and the substrate, according to an embodiment of the present disclosure. It is noted that 1A only four electrodes are illustrated, the description being purely exemplary, and structures such as the connection lines of the touch electrodes are omitted.

As in 1A and 1B 1, the touch sensor has a substrate 100, and the substrate 100 has a plurality of grooves 101 that have a stripe shape and cross each other to define a lattice shape, and touch electrodes 102 formed in the grooves 101. FIG. Since the touch electrodes 102 are formed in the grooves 101, the touch electrodes filled in the plurality of grooves crossing each other are electrically connected to form a touch electrode for detecting a touch position. The manner in which the grooves 101 cross each other depends on the shape of the required touch electrodes. As in 1A 1, five grooves extending along a first direction X and five grooves extending along a second direction Y are crossed with each other to form the shape of a touch electrode for position detection. However, the present disclosure does not limit either the shape formed by crossing the grooves or the number of the crossed grooves. The touch electrode 102 may be a self-capacitive or a counter-capacitive touch electrode. Is it the Touch electrode 102 around the counter-capacitive touch electrode, so the touch electrode 102 includes a touch control electrode and a touch detection electrode to realize the detection of the touch position, although the present disclosure is not limited in this respect.

According to 1B the touch sensor further includes a first propagation control layer 103 . The first spreading control layer 103 is arranged on an inner wall of the groove 101 and positioned between the groove 101 and the touch electrode 102 . As in 2A and 2 B 1, a spread angle between the touch electrode in a released state and the first spread control layer 103 is denoted by α, and a spread angle between the touch electrode in a released state and the substrate 100 is denoted by β, where α is not equal to β. The measurement of the propagation angle is based on the same environmental conditions. Optionally, α is smaller than β, which can be realized by appropriately forming the material of the first spreading control layer 103 or by applying a surface treatment to the surface of the substrate 100.

It is noted that surface spreading properties of matter refer to an ability of a liquid to maintain contact with a solid surface. This surface contact ability translates into a propagation angle between the liquid and the solid surface. The smaller the propagation angle, the stronger the ability of the liquid in contact with the solid surface, and thus the liquid spreads more easily on the solid surface. According to 2A Here, the propagation angle is defined as an included angle between a tangent T1 of a gas-liquid interface at a crossing point O of three phases, ie gas, liquid and solid, and a solid-liquid boundary line T2 passing through the liquid. If α is smaller than β, the surface spreading characteristics of the touch electrode in a dissolved state and the first spread control layer 103 are better than the spreading characteristics of the touch electrode in a dissolved state and the surface of a substrate 100. The advantages of such a configuration are, on the one hand, that when the electrode material solution is jet is discharged and printed outside the groove, since the spreading property of the electrode material solution to the substrate is inferior to the spreading property of the electrode material solution to the first spreading control layer in the groove, the electrode material solution tends to flow into the groove, thereby ensuring the reliability of the touch electrode manufacturing process. In another aspect, the electrode material solution has good spreading properties with respect to the first spreading control layer. Therefore, the electrode material solution can be evenly distributed in the groove, improving the uniformity of the touch electrode and ensuring good touch performance of the touch sensor.

Optionally, a magnitude relationship of the spread angle α between the touch electrode in the released state and the first spread control layer and the spread angle β between the touch electrode in the released state and the substrate satisfies the following condition:

$$0°\le \mathrm{a}\le 30°,60°\le \mathrm{\beta }\le 180°$$

When 0°≦α≦30°, the electrode material solution can be well spread on the surface of the first spreading control layer, and when 60°≦β≦180°, the electrode material solution can easily flow on the surface of the substrate. Optional applies

$$0°\le \mathrm{a}\le 10°,\text{9}0°\le \mathrm{\beta }\le 180°$$

When 0°≦α≦10°, the electrode material solution can be almost completely spread on the surface of the first spread control layer, and when 90°≦β≦180°, the electrode material solution is not or not fully spread on the surface of the substrate. There is then a significantly different spreading relationship between the electrode material solution on the surface of the first spreading control layer and the electrode material solution on the surface of the substrate. The touch electrode can be manufactured by spraying the electrode material solution all over the entire surface of the substrate. Due to the significantly different spreading relationship between the electrode material solution on the surface of the first spreading control layer and the electrode material solution on the surface of the substrate, droplets of the electrode material solution sprayed on the surface of the substrate can flow selectively into the groove by not spreading with respect to the substrate, and thereby the touch electrode with a form specific pattern, whereby the manufacturing cost is greatly reduced.

Optionally, the first spread control layer 103 covers the entire surface of the inner wall of the groove, so that the electrode material solution can be evenly distributed throughout the groove, thereby making the surface flat on the one hand Safety of the touch sensor is increased and, on the other hand, the uniformity of the touch electrode in the groove is improved, thereby reducing the risk of breakage of the touch electrode.

Further according to 1 B a depth d1 of the groove 101 is less than a thickness D of the substrate 100 and a thickness d2 of the first spreading control layer is less than the depth d1 of the groove 101. The depth d1 of the groove 101 is less than the thickness D of the substrate and the groove 101 does not penetrate the substrate 100 completely, so that the substrate 100 can better accommodate the touch electrode. The thickness d2 of the first diffusion control layer is smaller than the depth d1 of the groove 101, which ensures that the first diffusion control layer 103 does not fill the groove completely, so that the touch electrode is formed in the groove and the touch sensor has better surface flatness. Optionally, the thickness of the substrate is 1 to 50 µm, the depth of the groove is 0.5 to 8 µm, and the thickness of the first spreading control layer is 0.01 to 1 µm.

3A 12 is a schematic representation of a groove according to an embodiment of the present disclosure. 3B 12 is a schematic representation of another groove according to an embodiment of the present disclosure and 3C 12 is a cross-sectional view taken along AA 3B . As in 3A and 3B As shown, the groove 101 has a side wall 101a extending along a strip-like extension direction of the groove, the side wall 101a being a curved surface. In this embodiment, the side wall 101a of the groove 101 is formed as a curved surface. The first spreading control layer is arranged on the surface of the inner wall of the groove. The first spreading control layer has a curved surface that conforms in shape to the inner wall of the groove. The shape of the groove as a curved surface can reduce an intensity of pressure of the electrode material solution flowing in the groove exerted over the groove. An inclination of the curved surface of the groove causes the pressure exerted by the side wall of the groove on the electrode material solution to generate a component of the pressure of the electrode material solution, and reduces an immediate stress of the liquid on the groove, thereby reducing a pressure differential resistance, so that the Resistance of the liquid can be effectively reduced and the flow of the electrode material solution is accelerated, thereby enabling a more advantageous distribution of the electrode material solution in the groove.

As in 3C shown, the curved surface optionally has a plurality of first tangent planes (e.g., S1, S2...Sn in 3C ) on. Gradients k1, k2...kn of the plurality of first tangent planes gradually decrease in the direction from the bottom of the groove to the top of the groove.

It is therefore k1 > k2 > ... > kn.

When gradients k1, k2 and kn of the plurality of first tangent planes in the direction from the bottom of the groove to the top of the groove satisfy the above conditions, the curved surfaces of the side walls of the groove protrude toward the top of the groove. A pressure difference resistance of the side walls of the groove to the liquid flowing in the groove is then the smallest, the spread control layer 103 arranged in the groove ensures a uniform distribution of the electrode material solution and the curved surfaces of the side walls of the groove maximize the flowability of the electrode material solution in the groove, whereby the Processing reliability of the touch electrode is ensured.

As in 3C 1, the number of side walls 101a of the groove 101 is two, and the two side walls 101a of the groove 101 cross each other at the bottom of the groove 101, so that the formed bottom of the groove is not a flat surface and that on the surfaces of the side walls 101a of the groove formed first spreading control layer 103 has a component of the pressure exerted by the side wall of the groove on the electrode material solution at each position, thereby further reducing the resistance of the side walls of the groove to the electrode material solution and increasing the fluidity of the electrode material solution in the groove 101.

In the embodiments of the present disclosure, the first diffusion control layer 103 optionally covers the entire surface of the inner wall of the groove 101. Since the first diffusion control layer 103 has a diffusion-regulating effect on the electrode material solution dripping into the groove, it becomes good and uniform in fluidity of the electrode material solution in the groove when the first spreading control layer 103 covers the entire surface of the inner wall of the groove. It is noted that an embodiment of the present disclosure may also provide that the first propagation control layer 103 covers a part of the surface of the inner wall of the groove 101, but the present disclosure is not limited in this regard.

The first propagation control layer 103 may be made of an inorganic material. When the material of the first spreading control layer 103 is the inorganic material, the first Spreading control layer with respect to the electrode material solution good spreading properties. When the electrode material layer flows on the surface of the first spreading control layer 103, the electrode material solution can be spread evenly on the surface of the first spreading control layer 103. By way of example, the inorganic material may be at least one of silicon nitride, silicon oxide, silicon oxynitride, aluminum oxide, or titanium dioxide. The material of the first spreading control layer can also be an organic material. When the material of the first spreading control layer is the organic material, the spreading control layer has poor spreading properties with respect to the electrode material solution. In this case, the electrode material solution can smoothly flow on the surface of the first spreading control layer 103, which is beneficial to the manufacturing process of the touch electrode. By way of example, the organic material includes at least one of the following: polytetrafluoroethylene, perfluoroalkoxylalkane, perfluoroethylene-propylene copolymer, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polychlorotrifluoroethylene, ethylene-trifluoroethylene copolymer, polytetrachloroethylene-perfluorodioxole copolymer, and polyvinyl fluoride.

4 12 is a schematic representation of another groove according to an embodiment of the present disclosure. As in 4 1, a second spreading control layer 104 is further provided on the surface of the inner wall of the groove 101. As shown in FIG. The first spread control layer 103 does not completely overlap with the second spread control layer 104. A spread angle between the touch electrode in a released state and the second spread control layer 104 is denoted by α1, and a spread angle between the touch electrode in a released state and the first spread control layer 103 is denoted by α, where α1 is not equal to α. In this embodiment, the spread angle between the touch electrode in the dissolved state and the first spread control layer 103 is different from the spread angle between the touch electrode in the dissolved state and the second spread control layer 104, whereby regulation of the flowability and spreadability of the electrode material solution can be realized at the same time.

In concrete terms, the liquid can be spread evenly on the solid surface and thus has good spreading ability when the spreading angle between the liquid and the solid surface is smaller. If the propagation angle between the liquid and the solid surface is larger, it means that the liquid is not readily compatible with the solid surface. The liquid then has good flow properties on the solid surface. In this embodiment, two types of spread control layers different in spread angle are simultaneously arranged in the groove, thereby enabling both good spreadability of the electrode material solution in the groove and accelerated flowability of the electrode material solution in the groove. Good fluidity facilitates the processing of the touch electrode and allows the locally dropped electrode material solution to flow smoothly and spread evenly, thereby enhancing the overall uniformity of the touch electrode. When the electrode material solution on the surfaces of the first spreading control layer 103 and the second spreading control layer 104 has a larger spreading angle difference, the first spreading control layer 103 and the second spreading control layer 104 have a good regulating effect on the flowability and spreadability of the electrode material solution.

The numerical range of the propagation angle α between the touch electrode in the released state and the first spread control layer 103 is 0° ≤ α ≤ 30°, and the numerical range of the propagation angle α1 between the touch electrode in the released state and the second spread control layer 104 is 60° ≤ α1 ≤ 180 °. When 0°≦α≦30°, the electrode material solution can be spread well on the surface of the first spreading control layer 103, and when 60°≦α1≦180°, the electrode material solution can easily flow on the surface of the second spreading control layer 104.

The numerical range of the propagation angle α between the touch electrode in the released state and the first spread control layer 103 is 0° ≤ α ≤ 10°, and the numerical range of the propagation angle α1 between the touch electrode in the released state and the second spread control layer 104 is 90° ≤ α1 ≤ 180 °. When 0° ≤ α ≤ 10°, the electrode material solution can be almost completely spread on the surface of the first spreading control layer and has good spreadability, and when 90° ≤ α1 ≤ 180°, the electrode material solution is not or not completely spread on the surface of the second spreading control layer 104, but has the best fluidity. It is noted that when the propagation angle between the touch electrode in the dissolved state and the first spread control layer 103 is less than that between the touch electrode in the dissolved state and the second spread control layer 104, the second spread control layer may be the same material as the substrate, and the spread angle between the touch electrode in the dissolved state state and the substrate may be the same or approximately the same as the propagation angle between the touch electrode in the dissolved state and the second propagation control layer 104 .

If the propagation angle between the touch electrode in the released state and the first spread control layer 103 is smaller than that between the touch electrode in the released state and the second spread control layer 104, the material of the first spread control layer may be inorganic material and the material of the second spread control layer may be inorganic trade organic material. When the spread angle between the touch electrode in the released state and the first spread control layer 103 is larger than that between the touch electrode in the released state and the second spread control layer 104, the material of the first spread control layer can be the organic material and the material of the second spread control layer be the inorganic material. The inorganic material includes at least one of silicon nitride, silicon oxide, silicon oxynitride, aluminum oxide, or titanium dioxide. The organic material includes at least one of the following: polytetrafluoroethylene, perfluoroalkoxylalkane, perfluoroethylene-propylene copolymer, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polychlorotrifluoroethylene, ethylene-trifluoroethylene copolymer, polytetrachloroethylene-perfluorodioxole copolymer, and polyvinyl fluoride.

As in 4 As shown, the first propagation control layer 103 and the second propagation control layer 104 together cover the inner wall of the groove 101. A thickness of the first propagation control layer 103 is equal to the thickness of the second propagation control layer 104. 4 11 illustrates that the first propagation control layer 103 is placed at the bottom of the groove, while the second propagation control layer is placed on sidewalls on two sides of the groove. In an optional implementation of this embodiment, the second propagation control layer 104 is alternatively arranged at the bottom of the groove and the second propagation control layer 103 is arranged on side walls on two sides of the groove, or the first propagation control layer 103 and the second propagation control layer 104 are arranged alternately on the surface of the inner wall of the groove , the present disclosure being not limited in this regard. By concurrently forming the first spreading control layer and the second spreading control layer, regulation of fluidity and spreadability of the electrode material solution in the groove can be realized, and stability in formation of the touch electrode is ensured.

In the embodiments of the present disclosure, the material of the substrate may be an organic material, the substrate may be formed by ink jet printing, and the grooves on the surface of the substrate may be formed at the same time during manufacturing of the substrate.

5 10 shows a touch display panel including one of the touch sensors described above, according to an embodiment of the present disclosure. The touch display panel may be an organic light emitting display panel including an organic light emitting device 110 and a thin film encapsulation layer 111 covering the organic light emitting device 110 . The touch sensor TS is formed directly on the surface of the thin film encapsulation layer 111 .

The touch display panel provided by this embodiment may be an organic light emitting diode display panel. The touch display panel includes a substrate 120, which may be a flexible substrate. The flexible substrate may be formed from any suitable flexible insulating material. For example, the flexible substrate may be formed from polymeric materials such as polyimide (PI), polycarbonate (PC), polyethersulfone (PES), polyethylene terephthalate (PET), polyethylene naphthalene (PEN), polyarylate (PAR), or a fiberglass-plastic composite (FRP). The flexible substrate can be transparent, semi-transparent, or non-transparent. The flexible substrate enables the touch display panel to be implemented as a display flexible such as by bending, twisting, and buckling.

A buffer layer 121 is positioned on the flexible substrate. The buffer layer 121 can cover the entire top of the flexible substrate. In one embodiment, the buffer layer has an inorganic layer or an organic layer. For example, the buffer layer can be formed by materials selected from inorganic materials such as silicon oxide (SiO _x ), silicon nitride (SiN _x ), silicon oxynitride (SiO _x N _y ), aluminum oxide (AlO _x ) or aluminum nitride (AlN _x ) or from organic materials such as acrylic, polyimide (PI) or polyester. The buffer layer 121 may have a single layer or a plurality of layers. The buffer layer keeps oxygen and moisture out and prevents moisture or contaminants from diffusing through the flexible substrate and provides a flat surface on top of the flexible substrate.

A thin film transistor (TFT) is positioned on the buffer layer 121 . In the embodiments of the present disclosure, the structure is explained by taking a top gate TFT as an example.

The TFT has a semiconductor active layer 122 positioned on the buffer layer 121 . The semiconductor active layer 122 has a source region 122a and a drain region 122b formed by doping n-type impurity ions or p-type impurity ions. A region located between the source region 122a and the drain region 122b constitutes a channel region 122c not doped with impurity ions.

The semiconductor active layer 122 can be formed by crystallization of amorphous silicon so that the amorphous silicon is converted into polysilicon.

Various methods can be used to crystallize the amorphous silicon, such as Rapid Thermal Annealing (RTA), Solid Phase Crystallization (SPC), Excimer Laser Annealing (ELA), Metal Induced Crystallization, MIC), Metal Induced Lateral Crystallization (MILC) or Sequential Lateral Solidification (SLS) etc.

A gate insulating layer 123 comprises an inorganic layer such as silicon oxide, silicon nitride, or metal oxide, and may comprise a single layer or a plurality of layers.

A gate electrode 124 is positioned in a specific region on the gate insulating film 123 . The gate electrode 124 can be a single layer or multiple layers of gold (Au), silver (Ag), copper (Cu), nickel (Ni), platinum (Pt), palladium (Pd), aluminum (Al), molybdenum (Mo) or chromium (Cr) or an alloy such as an aluminum (Al) neodymium (Nd) alloy or a molybdenum (Mo) tungsten (W) alloy.

An insulating interlayer 125 is positioned on the gate electrode 124 . The interlayer insulating layer 125 may be formed by an inorganic insulating layer made of silicon oxide or silicon nitride. Optionally, the insulating interlayer can be formed by an insulating organic layer.

On the insulating interlayer 125, a source electrode 126 and a drain electrode 127 are positioned. The source electrode 126 and the drain electrode 127 are electrically connected (or coupled) via a contact hole to the source region and the drain region, respectively. The contact hole is formed by selectively removing the gate insulating film and the interlayer insulating film.

A passivation layer 128 is positioned on the source and drain electrodes. The passivation layer 128 may be formed by an inorganic layer of silicon oxide or silicon nitride, or an organic layer.

A planarization layer 129 is positioned on the passivation layer 128 . The planarization layer 129 comprises an acrylic, polyimide (PI) or benzocyclobutene (BCB) organic layer. The planarization layer 129 has a planarization function.

An organic light emitting device is formed on the TFT.

A thin film encapsulation layer is positioned on the organic light emitting device. In one embodiment, the thin-film encapsulation layer protects a light-emitting layer and other thin layers from moisture and oxygen, etc.

In general, the touch sensor formed directly in the touch display panel is formed by evaporation and etching. These processes include a wet process such as cleaning. The thin film encapsulation layer is required to have excellent water vapor and oxygen barrier properties to ensure that the wet process does not have any harmful effect on the organic light-emitting device in the thin film encapsulation layer, which undoubtedly involves high manufacturing costs. The structure of the touch sensor TS provided by the present disclosure can be formed by ink jet printing. Thus, when the touch sensor TS is formed directly on the surface of the thin-film encapsulation layer, it does not adversely affect the layer of light-emitting elements, so that lower demands on the encapsulation properties of the thin-film encapsulation layer exist. The touch sensor TS has a substrate which has a multiplicity of intersecting strip-shaped grooves which represent a lattice shape. A touch electrode is filled in the groove, and between the groove and the touch electrode is provided a first spreading control layer sandwiched between the groove and the touch electrode. The touch electrode is formed in the groove by ink jet printing. The first spread control layer can regulate the flowability as well as the spreading ability of the touch electrode in the groove. The formed touch electrode has good processing stability. The touch electrode is formed in the groove, and the surface of the touch sensor TS has high flatness, thereby providing favorable conditions for subsequent layering processes of the touch display panel. The substrate has a multiplicity of grooves, whereby the bending strength of the touch sensor is increased, so that it is advantageously suitable for forming the touch display panel as a flexible display.

Basically, metallic materials are selected for the touch electrode. In the embodiments of the present disclosure, by directly forming the touch sensor TS having the structure described above on the surface of the thin film encapsulating layer, the overall thickness of the touch display panel can be reduced and integration of the display panel and the touch sensor can be implemented. The touch sensor TS formed on the thin film encapsulation layer is positioned between a circular polarizer and the light emitting element layer of the touch display panel, thereby reducing reflection of external ambient light at the metal touch electrode and graphic visibility.

6 FIG. 12 shows another touch display panel according to an embodiment of the present disclosure. In contrast to the in 5 In the embodiment shown, the thin film encapsulation layer 111 comprises at least one organic layer 111a and at least two inorganic layers 111b. The organic layer 111a is positioned between the two inorganic layers 111b. The substrate of the touch sensor TS is the organic layer 111a. In this embodiment of the present disclosure, the touch electrode is disposed in the thin film encapsulation layer and the organic layer doubles as the substrate of the touch sensor. On the one hand, corrosion of outside water vapor and oxygen on the touch electrode can be prevented, and on the other hand, the thickness of the touch display panel can be further reduced, which corresponds to the development trend toward light weight and thin design. The touch electrode is arranged in the first groove of an organic layer of the thin film encapsulation layer. This can significantly reduce the risk of breakage of the touch electrode during bending.

The present disclosure further provides a method of manufacturing a touch sensor. 7 FIG. 1 is a schematic flowchart of a method of manufacturing a touch sensor according to an embodiment of the present disclosure. As in 7 shown, the manufacturing process includes the following:

S01: forming a substrate 100,

forming a plurality of stripe-shaped grooves 101 on a surface of the substrate 100, the plurality of grooves intersecting each other to define a lattice shape,

S02: forming a first propagation control layer 103, wherein the first propagation control layer 103 is formed on an inner wall of the groove 101, and

S03: forming a touch electrode 102, in which the touch electrode 102 is filled in the groove 101 and the first spreading control layer 103 is positioned between the groove 101 and the touch electrode 102.

An angle of spread between the touch electrode 102 in a released state and the first spread control layer 103 is denoted by α, and an angle of spread between the touch electrode 102 in a released state and the substrate 100 is denoted by β, where α is not equal to β.

In step S01, the substrate 100 and the groove 101 can be formed on the surface of the substrate 100 at the same time by ink jet printing. The material of the substrate 100 is dissolved in a solvent to form an ink droplet solution of the substrate, and the ink droplet solution is ejected as a jet, and the ejected ink droplet solution is cured. In this way, the substrate and the groove are formed. The shape and the depth of the formed groove can be controlled by controlling an ink droplet size of the ink droplet solution jetted and the curing time of the ink droplet solution. By using the ink jet printing, the thickness of the formed substrate, the shape of the groove, a pitch of the grooves, and the like can be freely and flexibly controlled. The substrate and the groove on the surface of the sub strats can be formed in one go without multi-step processes such as evaporation and etching.

The step of forming the first propagation control layer 103 in step S02 includes: forming the entire first propagation control layer on the surface of the substrate 100, etching the entire first propagation control layer so that in the groove 101 the first propagation control layer is formed.

The touch electrode forming step in step S03 includes: dissolving the material of the touch electrode in the organic solvent to form electrode material solution of the touch electrode, and jetting the electrode material solution into the groove by ink jet printing.

Basically, the touch electrode of the touch sensor is formed directly on the surface of the substrate of the touch sensor. The touch electrode material comprises transparent indium tin oxide. However, in a flexible display panel, a metal mesh electrode with good flexibility and lower impedance can be used to increase the flexural strength of the touch electrode. In the manufacturing process of the metal grid, a screen printing process can be used with the direct application of metal printing ink. Alternatively, the metal can be applied as a full coating to the substrate as a thin film and then superfluous parts washed away via a yellow light photolithography process to create the grating. Any of the above approaches may have a detrimental effect on the light-emitting element when the metal mesh electrode is formed directly in the organic light-emitting display panel.

In the embodiments of the present disclosure, the touch electrode is formed in the groove on the substrate by ink jet printing. The groove can be a strip-shaped groove. Further, a plurality of stripe-shaped grooves cross each other to form a lattice shape. The number of grooves crossing each other and the shape of the lattice formed by crossing depend on the shape of the touch electrode used for touch position detection. The electrode material of the touch electrode can be metal and optionally metallic materials such as gold, silver or copper etc. The organic solvent is one of the following: ethyl cellulose, cellulose nitrate, polyvinyl acetate, ketone resin, and polyphthaleinamine resin. The electrode material of the touch electrode is dissolved in the organic solvent to form the electrode material solution of the touch electrode, and then the electrode material solution is jetted and printed in the groove of the substrate. The electrode material solution can be jetted and printed in the crossing region of the groove, so that liquid flowing into the groove flows smoothly along the inner wall of the groove to form a uniform electrode shape, which is then cured, and the organic solvent volatilizes. In this way, the touch electrode is formed.

In the embodiments of the present disclosure, a first spread control layer is formed on the inner wall of the groove before the electrode material solution is jetted and printed in the groove. The first spreading control layer can regulate spreading properties of the electrode material solution with respect to the groove. In this way, a flow rate and uniform distribution of the electrode material solution in the groove are regulated and controlled, uniformity of the formed touch electrode is ensured, a risk of disconnection of the touch electrode is reduced, uniform impedance of each electrode is ensured, and touch performance of the touch sensor is improved.

The material of the first propagation control layer 103 may be inorganic. When the material of the first spreading control layer 103 is the inorganic substance, the first spreading control layer has good spreading properties with respect to the electrode material solution. When the electrode material solution flows on the surface of the first spreading control layer 103, the electrode material solution can be uniformly spread on the surface of the first spreading control layer 103. By way of example, the inorganic material can be at least one of silicon nitride, silicon oxide, silicon oxynitride, aluminum oxide or titanium dioxide. The material of the first propagation control layer can also be an organic substance. When the material of the first propagation control layer is the organic substance, the first propagation control layer has poor propagation properties with respect to the electrode material solution. In this case, the electrode material solution can smoothly flow on the surface of the first spreading control layer 103, which is beneficial to the manufacturing process of the touch electrode. By way of example, the organic substance has at least one of the following: polytetrafluoroethylene, perfluoroalkoxylalkane, perfluoroethylene-propylene copolymer, ethylene-tetrafluoroethylene copolymer, polyvinyl denfluoride, polychlorotrifluoroethylene, ethylene-trifluoroethylene copolymer, polytetrachloroethylene-perfluorodioxole copolymer and polyvinyl fluoride.

It is noted that the above embodiments are merely preferred embodiments of the present disclosure and the technical principles applied thereby. Those skilled in the art will understand that the present disclosure is not limited to the specific embodiments described herein and that various obvious changes, adaptations, and substitutions can be made without departing from the scope of the present disclosure. Therefore, although the present disclosure is referred to in detail in the above embodiments, it is not limited only to the above embodiments, but more equivalent embodiments may be included without departing from the basic concept of the present disclosure, the scope of the present invention is based on the scope of the appended claims.

Claims (20)

Touch sensor, which includes: a substrate (100) comprising a plurality of grooves (101) having a stripe shape and crossing each other to form a lattice shape, a first spreading control layer (103) disposed on an inner wall of each of the plurality of grooves (101), and a touch electrode (102) filled in the groove (101), the first spreading control layer (103) being disposed between the groove (101) and the touch electrode (102), wherein a spread angle between the touch electrode (102) in a released state and the first spread control layer (103) is denoted by α and a spread angle between the touch electrode (102) in a released state and the substrate (100) is denoted by β, where α is not equal to β, and the touch electrode (102) in a dissolved state is a solution formed by dissolving electrode material of the touch electrode (102) in a solvent, wherein the propagation angle in the dissolved state is defined as an angle between a tangent (T1) of a gas-liquid interface at a crossing point (O) of the gas phase, the liquid phase and the solid phase, and a solid line passing through the liquid Liquid boundary line (T2) included angle. touch sensor after claim 1 wherein a depth of the groove (101) is less than a thickness of the substrate (100) and a thickness of the first spreading control layer (103) is less than the depth of the groove (101). touch sensor after claim 1 , wherein the groove (101) has a side wall extending along a strip-like extension direction of the groove (101), and the side wall is a curved surface. touch sensor after claim 3 wherein the curved surface has a plurality of first tangent planes, gradients of the plurality of first tangent planes gradually decreasing in a direction from a bottom of the groove (101) to a top of the groove (101). touch sensor after claim 4 wherein the groove (101) has two side walls (101a), and the two side walls (101a) cross each other at the bottom of the groove (101). touch sensor after claim 1 wherein the first spreading control layer (103) covers the entire surfaces of the inner wall of the groove (101). touch sensor after claim 1 , where α is smaller than β. touch sensor after claim 7 , whereby $$0°\le \mathrm{a}\le 30°,60°\le \mathrm{\beta }\le 180°$$

touch sensor after claim 8 , whereby $$0°\le \mathrm{a}\le 10°,\text{9}0°\le \mathrm{\beta }\le 180°$$

touch sensor after claim 1 , further comprising: a second propagation control layer (104) disposed on the inner wall surface of the groove (101), wherein the first propagation control layer (103) and the second propagation control layer (104) do not completely intersect each other and a propagation angle between the touch electrode (102) in the released state and the second spread control layer (104) is denoted by α1 and α1 is not equal to α. touch sensor after claim 10 , where α is smaller than α1. touch sensor after claim 11 , whereby $$0°\le \mathrm{a}\le 30°,60°\le \mathrm{a}1\le 180°$$

touch sensor after claim 1 , wherein the touch electrode (102) consists of a metal material and the organic solvent is selected from one of the following: ethyl cellulose, cellulose nitrate, polyvinyl acetate, ketone resin and polyamide resin. touch sensor after claim 10 wherein the first propagation control layer (103) is made of organic material and the second propagation control layer (104) is made of inorganic material, or the first propagation control layer (103) is made of an inorganic material and the second propagation control layer (104) is made of an organic material. Touch display panel, which includes: the touch sensor claim 1 an organic light emitting device (110), and a thin film encapsulating layer (111) covering the organic light emitting device (110), wherein the touch sensor is formed directly on a surface of the thin film encapsulating layer (111). A method of making a touch sensor, comprising: forming a substrate (100), forming a plurality of stripe-shaped grooves (101) on a surface of the substrate (100), the plurality of grooves (101) crossing each other to form a lattice shape, forming a first propagation control layer (103), the first propagation control layer (103) being formed on an inner wall of each of the plurality of grooves (101), forming a touch electrode (102), the touch electrode (102) being filled in the groove (101) with the first spreading control layer (103) interposed between the groove (101) and the touch electrode (102), wherein a spread angle between the touch electrode (102) in a released state and the first spread control layer (103) is denoted by α and a spread angle between the touch electrode (102) in a released state and the substrate (100) is denoted by β, where α is not equal to β, and the touch electrode (102) in a dissolved state is a solution formed by dissolving electrode material of the touch electrode in a solvent, wherein the propagation angle in the dissolved state is defined as an angle between a tangent (T1) of a gas-liquid interface at a crossing point (O) of the gas phase, the liquid phase and the solid phase, and a solid line passing through the liquid Liquid boundary line (T2) included angle. procedure after Claim 16 wherein the steps of forming the substrate (100) and the groove (101) comprise: forming the substrate (100) and the groove (101) by ink jet printing. procedure after Claim 17 wherein the ink jet printing method comprises: forming an ink droplet solution of the substrate (100), jetting the ink droplet solution, and curing the ink droplet solution. procedure after Claim 16 , wherein the step of forming the first propagation control layer (103) comprises: forming the entire first propagation control layer (103) on the surface of the substrate (100), etching the entire first propagation control layer (103) so that the first propagation control layer (103) in of the groove (101) is formed. procedure after Claim 16 wherein the step of forming the touch electrode (102) comprises: dissolving the material of the touch electrode (102) in an organic solvent to form electrode material solution of the touch electrode (102), and jetting the electrode material solution into the groove (101) by means inkjet printing.

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